Firstly, the abbreviations used in this specification are described.    HA: hyaluronic acid    HAS: hyaluronic acid synthase
The following describes on the techniques related to the present invention.
Patent Reference 1 and Patent Reference 2 disclose a heavy metal salt of HA, wherein the metal is selected from silver, gold, cerium and tungsten, and a method for inhibiting growth of a microorganism, which comprises allowing the microorganism to contact with an effective amount of silver HA. Additionally, it is described that the silver HA inhibits growth of Candida albicans and Candida tropicalis. 
Patent Reference 3 and Patent Reference 4 disclose pharmaceutical compositions having anti-microbial activity, which comprise an HA-zinc associated compound (complex) or an HA-cobalt associated compound (complex) as the active ingredient. Also, it is described that although a zinc HA solution induced several figures of reduction of a large number of organisms tested (including Candida albicans and Aspergillus niger), the number of the organisms tested did not change significantly in a sodium HA. Additionally, it is described also that the sodium HA solution did not show its inhibitory effect upon any one of the organisms tested even when the concentration is 2000 μg/mL.
Patent Reference 5 and Patent Reference 6 disclose the use of one compound or several compounds selected from the group consisting of carbohydrates or carbohydrate derivatives, as the anti-adhesive active ingredient for a microorganism or the like. Additionally, HA is described as an example of the carbohydrates, and a fungus, Candida albicans or the like is described as an example of the microorganism. However, there is no disclosure on the specific pharmacological test result of their drug effect, and it is not described clearly that the method can be used.
Although non-patent Reference 1 discloses on the bacteriostatic activity of HA, there is no description or suggestion regarding fungi and the genus Candida. 
There is a description in Non-patent Reference 2 on the bacteriostatic test (including Candida albicans) of sodium HA. However, it is concluded as a result that sodium HA does not have the bacteriostatic activity since the microorganisms properly grew in a medium containing sodium HA.    Patent Reference 1: Japanese Patent No. 2613605    Patent Reference 2: U.S. Pat. No. 4,746,504    Patent Reference 3: JP-T-2001-500860    Patent Reference 4: U.S. Pat. No. 6,348,190    Patent Reference 5: JP-T-10-513165    Patent Reference 6: International Publication WO 96/23479    Non-patent Reference 1: Pimazar P. et al., 1999, Journal of Periodontology, vol. 70, no. 4, p. 370-374    Non-patent Reference 2: Tang Z. H. et al., 2002, Zhongguo Xiu Fu Chong Jiam Wai Ke Za Zhi, vol. 16, no. 4, p. 259-261